U.S. Pat. No. 4,570,662, issued Feb. 18, 1986 and assigned to the assignee of this invention, describes a demand responsive flow control valve between a pump and a motor vehicle power steering gear which regulates a high flow and a low flow in a fluid conduit between the pump and the steering gear depending upon the magnitude of a system pressure downstream of a flow control orifice in the fluid conduit. In the absence of demand for power assist, the system pressure is low and low flow prevails. When power assist is demanded, the system pressure is higher and high flow prevails. The effective area of the flow control orifice is selected in combination with other system variables to achieve a high flow corresponding to predetermined performance characteristics of the steering system. Parasitic losses, e.g., fluid friction, associated with the corresponding low flow consume power and reduce fuel economy of the motor vehicle. U.S. Pat. No. 4,570,667, issued Feb. 18, 1986 and assigned to the assignee of this invention, describes an improved demand responsive flow control valve having a valve pintle which strokes linearly to an active position obstructing the flow control orifice when the aforesaid system pressure is low and which strokes linearly to an inactive position removed from the flow control orifice when the system pressure increases to a higher transition magnitude. When the flow control orifice is obstructed, its effective area and corresponding low flow and parasitic losses are all reduced compared to the effective area and corresponding low flow and parasitic losses of the unobstructed flow control orifice. With this construction, however, the active position of the valve pintle is defined by an integral stop on a housing of the valve, the location of which stop may vary within a range dictated by manufacturing tolerance. Because the location of the integral stop may vary from valve to valve, the corresponding low flows may likewise vary from valve to valve.